Showing posts with label FPS. Show all posts
Showing posts with label FPS. Show all posts

Thursday, December 17, 2015

Differences H.265 and H.264

Differences between H.265 and H.264



A codec is an encoder and a decoder. An encoder compresses audio or video so it takes up less disk space. A decoder extracts audio or video information from the compressed file. Video and audio compression is a complex technical process, but the basic aim of a codec is quite straightforward:

(a) Reduce the size of the compressed media file as much as possible, but...(b) Keep the quality of the decoded audio and video as good as possible.

What is H.264?
H264 (aka MPEG-4 AVC) is currently a mainstream video compression format. It is widely used in Blu-ray discs, internet sources like videos in YouTube and iTunes Store, web software, and also HDTV broadcasts over terrestrial, cable and satellite.

What is H.265?
H.265 (also known as HEVC, short for High Efficiency Video Coding, developed by the Joint Collaborative Team on Video Coding (JCT-VC)) is a video compression standard whose predecessor is H.264/MPEG-4 AVC. H.265 HEVC ensures to deliver video quality identical to H.264 AVC at only half the bit rate, including better compression, delicate image and bandwidth saving. It Support up to 8K, Support up to 300 fps. It is likely to implement Ultra HD, 2K, 4K for Broadcast and Online (OTT).

H.265 vs H.264: Differences between H.265 and H.264

In general, H.265 has several big advantages over H.264, including better compression, delicate image and bandwidth saving. For more detailed differences, please read H.265 vs H.264 comparison table.

4 pcs 2MP IP cameras for 1 month, stream: 4096Kbps. 
H.264 IP camera need 42G×4×30=5T=1×3T+1×2T, so need 1 pc 3T and 1pc 2T HDD. 
H.265 IP camera need 21G×4×30=2.5T, so need 1 pc 3T HDD only, save at least 1 pc 2T HDD cost. 

Tuesday, June 12, 2012

Choosing a Frame Rate on CCTV

Movies on film are almost exclusively projected at 24 FPS. Television, however, does not have an internationally accepted frame rate. In Europe and many other countries, PAL and SECAM use 25 FPS, whereas NTSC video in North America and Japan uses 29.97 FPS. Other common frame rates are usually multiples of these.
Note: Converting video formats from one frame rate to another is technically challenging, and there are often unwanted visual side effects. This is especially true when the frame rates do not evenly divide. For example, converting 30 FPS to 60 FPS is fairly easy to do, but converting 29.97 FPS to 25 FPS is much more difficult. Making sure audio stays in sync throughout the conversion is yet another challenge.
Some digital video formats support several frame rates within a single format, allowing variable frame rate video recording and film (24 FPS) compatibility.
Frame rate
Media
Description
24 fps
Film; high definition video
This is the universally accepted film frame rate. Movie theaters worldwide almost always use this frame rate. Many high definition formats can record and play back video at this rate, though 23.98 is usually chosen instead (see below).
23.98 (23.976) fps
Film; high definition video with NTSC compatibility; NTSC
This is 24 fps slowed down by 99.9% (1000/1001) to easily transfer film to NTSC video. Many high definition video formats (and some SD formats) can record at this speed, and it is usually preferred over true 24 fps because of NTSC compatibility.
25FPS
PAL; high definition video
The European video standard. Film is sometimes shot at 25 FPS when destined for editing or distribution on PAL video.
29.97 fps
NTSC; high definition video
This has been the color NTSC video standard since 1953. This number is sometimes inaccurately referred to as 30 fps.
30 fps
High definition video; early black-and-white NTSC video
Some high definition cameras can record at 30 fps, as opposed to 29.97 fps. Before color was added to NTSC video signals, the frame rate was truly 30 fps. However, this format is almost never used today.
50 fps
PAL; high definition video
This refers to the interlaced field rate (double the frame rate) of PAL. Some 1080i high definition cameras can record at this frame rate.
59.94 fps
High definition video with NTSC compatibility
High definition cameras can record at this frame rate, which is compatible with NTSC video. It is also the interlaced field rate of NTSC video. This number is sometimes referred to as 60 fps, but it is best to use 59.94 FPS unless you really mean 60 FPS.
60 fps
High definition video
High definition equipment can often play and record at this frame rate, but 59.94 FPS is much more common because of NTSC compatibility.
Important: Many people round 29.97 FPS to 30 FPS, but this can lead to confusion during post-production. Today, it is still very rare to use a frame rate of 30 FPS, but very common to use 29.97 FPS. When in doubt, ask people to clarify whether they really mean 30 FPS, or if they are simply rounding 29.97 FPS for convenience.

Wednesday, February 29, 2012

Video Servers Bridge The Gap


Network IP solutions are touted as the answer for security problems, but analog cameras dominate most existing camera configurations. Video servers span the distance between analog and digital systems, upgrading existing systems and holding tantalizing potential for newer uses.
One benefit of digital systems is faster response time, with video servers bridging the gap between legacy analog systems and digital IP systems. The universal function of a video server is to transform analog signals into digital signalsimportant in places with existing analog frameworks. 

Video servers, sometimes known as video encoders, bridge the gap between analog CCTV surveillance systems and digital IP based systems. Video servers are a great budget conscious, transitional product for those who are looking to gain some of the features and benefits of network based solutions but, aren’t ready to make the full jump.
If you’ve installed analog cameras in the past few years they’re going to be functional for quite some time.  There’s no need to shortchange that investment.  Video servers will allow you to maintain those analog CCTV cameras while enhancing your video surveillance system to provide the benefits of IP video.

Why Use A Video Server?
So you don’t have to discard your existing analog cameras! A video server allows your functioning analog CCTV video surveillance system to be integrated with a network video system. Gain the benefits of network video without having to replace what’s bought, paid for, and still working.
Coax Cable Is Expensive
Installing coaxial cable is expensive and once installed, hard to justify re-cabling with Cat 5. And with the average lifespan of an analog camera at 5 - 7 years, what fails first are the VCR’s and DVR’s used to record the video. Video servers not only allow you to keep existing analog equipment such as analog CCTV cameras and coaxial cabling but open up a true network video system because the video is consistently sent over an IP network.
A video server connects to an analog video camera via a coaxial cable and converts analog video signals into digital video streams that are then sent over a wired or wireless IP-based network (i.g., LAN, WLAN or Internet).
Video Server Advantages
  • Use of standard network and PC server hardware for video recording and management instead of DVR’s or VCR’s
  • Scalability in steps of one camera at a time
  • Possibility to record off site
  • Ability to remotely access and control analog cameras over an IP network
  • Future-proof because the system is expanded easily by incorporating IP Cameras
Video Server Components
  • Analog Video Input: For connecting analog camera using coaxial cable.
  • Processor: For running encoder’s operating system, networking & security functions, encoding analog video using various compression formats, and video analysis. The processor determines the performance of a video encoder measured in frames per second (FPS).
  • Memory: For storing firmware (computer program) using Flash, and for buffering of video sequences (using RAM).
  • Ethernet/Power over Ethernet Port: To connect to IP network for sending and receiving data, and for powering the unit and the attached camera if Power over Ethernet (PoE) is supported.
  • Input/Output (I/O) Connectors: For connecting external devices such as sensors, relays, and lights.
  • Audio In: For connecting a microphone or line-in equipment and audio out for connecting to speakers.
What To Consider When Choosing A Video Server
  • The number of supported analog channels
  • Image quality
  • Compression formats
  • Resolution
  • Frame rate & features such as pan/tilt/zoom support
  • Audio
  • Event management
  • Intelligent video
  • Power over Ethernet (PoE)
  • Security Functionally
IP Convergence
Video servers are a great problem solver when you’re faced with the challenge of migrating a large investment in analog CCTV cameras to IP video.  Next up I’ll go into more detail about a very important benefit that video servers provide - Event management and intelligent video capabilities with the ability to use advanced video monitoring software

Tuesday, August 16, 2011

NAS, DAS, or SAN? - Choosing the Right Storage Technology ?

Data is unquestionably the lifeblood of today's digital organization. Storage solutions remain a top priority in IT budgets precisely because the integrity, availability and protection of data are vital to business productivity and success. But the role of information storage far exceeds day to day functions. Enterprises are also operating in an era of increased uncertainty. IT personnel find themselves assessing and planning for more potential risks than ever before, ranging from acts of terrorism to network security threats. A backup and disaster recovery plan is essential, and information storage solutions provide the basis for its execution.

Businesses are also subject to a new wave of regulatory compliance legislation that directly affects the process of storing, managing and archiving data. This is especially true for the financial services and healthcare industries, which handle highly sensitive information and bear extra responsibility for maintaining data integrity and privacy.

Although the need for storage is evident, it is not always clear which solution is right for your organization. There are a variety of options available, the most prevalent being direct-attached storage (DAS), network-attached storage (NAS) and storage area networks (SAN). Choosing the right storage solution can be as personal and individual a decision as buying a home. There is no one right answer for everyone. Instead, it is important to focus on the specific needs and long-term business goals of your organization. Several key criteria to consider include:
• Capacity - the amount and type of data (file level or block level) that needs to be stored and shared
• Performance - I/O and throughput requirements
• Scalability - Long-term data growth
• Availability and Reliability - how mission-critical are your applications?
• Data protection - Backup and recovery requirements
• IT staff and resources available
• Budget concerns
While one type of storage media is usually sufficient for smaller companies, large enterprises will often have a mixed storage environment, implementing different mediums for specific departments, workgroups and remote offices. In this paper, we will provide an overview of DAS, NAS and SAN to help you determine which solution, or combination of solutions, will best help you achieve your business goals.


DAS: Ideal for Local Data Sharing Requirements

Direct-attached storage, or DAS, is the most basic level of storage, in which storage devices are part of the host computer, as with drives, or directly connected to a single server, as with RAID arrays or tape libraries. Network workstations must therefore access the server in order to connect to the storage device. This is in contrast to networked storage such as NAS and SAN, which are connected to workstations and servers over a network. As the first widely popular storage model, DAS products still comprise a large majority of the installed base of storage systems in today's IT infrastructures. Although the implementation of networked storage is growing at a faster rate than that of direct-attached storage, it is still a viable option by virtue of being simple to deploy and having a lower initial cost when compared to networked storage. When considering DAS, it is important to know what your data availability requirements are. In order for clients on the network to access the storage device in the DAS model, they must be able to access the server it is connected to. If the server is down or experiencing problems, it will have a direct impact on users' ability to store and access data. In addition to storing and retrieving files, the server also bears the load of processing applications such as e-mail and databases. Network bottlenecks and slowdowns in data availability may occur as server bandwidth is consumed by applications, especially if there is a lot of data being shared from workstation to workstation.

DAS is ideal for localized file sharing in environments with a single server or a few servers - for example, small businesses or departments and workgroups that do not need to share information over long distances or across an enterprise. Small companies traditionally utilize DAS for file serving and e-mail, while larger enterprises may leverage DAS in a mixed storage environment that likely includes NAS and SAN. DAS also offers ease of management and administration in this scenario, since it can be managed using the network operating system of the attached server. However, management complexity can escalate quickly with the addition of new servers, since storage for each server must be administered separately.

From an economical perspective, the initial investment in direct-attached storage is cheaper. This is a great benefit for IT managers faced with shrinking budgets, who can quickly add storage capacity without the planning, expense, and greater complexity involved with networked storage. DAS can also serve as an interim solution for those planning to migrate to networked storage in the future. For organizations that anticipate rapid data growth, it is important to keep in mind that DAS is limited in its scalability. From both a cost efficiency and administration perspective, networked storage models are much more suited to high scalability requirements.

Organizations that do eventually transition to networked storage can protect their investment in legacy DAS. One option is to place it on the network via bridge devices, which allows current storage resources to be used in a networked infrastructure without incurring the immediate costs of networked storage. Once the transition is made, DAS can still be used locally to store less critical data.
NAS: File-Level Data Sharing Across the Enterprise

Networked storage was developed to address the challenges inherent in a server- based infrastructure such as direct-attached storage. Network-attached storage, or NAS, is a special purpose device, comprised of both hard disks and management software, which is 100% dedicated to serving files over a network. As discussed earlier, a server has the dual functions of file sharing and application serving in the DAS model, potentially causing network slowdowns. NAS relieves the server of storage and file serving responsibilities, and provides a lot more flexibility in data access by virtue of being independent.

NAS is an ideal choice for organizations looking for a simple and cost-effective way to achieve fast data access for multiple clients at the file level. Implementers of NAS benefit from performance and productivity gains. First popularized as an entry-level or midrange solution, NAS still has its largest install base in the small to medium sized business sector. Yet the hallmarks of NAS - simplicity and value - are equally applicable for the enterprise market. Smaller companies find NAS to be a plug and play solution that is easy to install, deploy and manage, with or without IT staff at hand. Thanks to advances in disk drive technology, they also benefit from a lower cost of entry.

In recent years, NAS has developed more sophisticated functionality, leading to its growing adoption in enterprise departments and workgroups. It is not uncommon for NAS to go head to head with storage area networks in the purchasing decision, or become part of a NAS/SAN convergence scheme. High reliability features such as RAID and hot swappable drives and components are standard even in lower end NAS systems, while midrange offerings provide enterprise data protection features such as replication and mirroring for business continuance. NAS also makes sense for enterprises looking to consolidate their direct-attached storage resources for better utilization. Since resources cannot be shared beyond a single server in DAS, systems may be using as little as half of their full capacity. With NAS, the utilization rate is high since storage is shared across multiple servers.

The perception of value in enterprise IT infrastructures has also shifted over the years. A business and ROI case must be made to justify technology investments. Considering the downsizing of IT budgets in recent years, this is no easy task. NAS is an attractive investment that provides tremendous value, considering that the main alternatives are adding new servers, which is an expensive proposition, or expanding the capacity of existing servers, a long and arduous process that is usually more trouble than it's worth. NAS systems can provide many terabytes of storage in high density form factors, making efficient use of data center space. As the volume of digital information continues to grow, organizations with high scalability requirements will find it much more cost-effective to expand upon NAS than DAS. Multiple NAS systems can also be centrally managed, conserving time and resources.

Another important consideration for a medium sized business or large enterprise is heterogeneous data sharing. With DAS, each server is running its own operating platform, so there is no common storage in an environment that may include a mix of Windows, Mac and Linux workstations. NAS systems can integrate into any environment and serve files across all operating platforms. On the network, a NAS system appears like a native file server to each of its different clients. That means that files are saved on the NAS system, as well as retrieved from the NAS system, in their native file formats. NAS is also based on industry standard network protocols such as TCP/IP, FC and CIFS.

SANs: High Availability for Block-Level Data Transfer

A storage area network, or SAN, is a dedicated, high performance storage network that transfers data between servers and storage devices, separate from the local area network. With their high degree of sophistication, management complexity and cost, SANs are traditionally implemented for mission-critical applications in the enterprise space. In a SAN infrastructure, storage devices such as NAS, DAS, RAID arrays or tape libraries are connected to servers using Fibre Channel. Fibre Channel is a highly reliable, gigabit interconnect technology that enables simultaneous communication among workstations, mainframes, servers, data storage systems and other peripherals. Without the distance and bandwidth limitations of SCSI, Fibre Channel is ideal for moving large volumes of data across long distances quickly and reliably.

In contrast to DAS or NAS, which is optimized for data sharing at the file level, the strength of SANs lies in its ability to move large blocks of data. This is especially important for bandwidth-intensive applications such as database, imaging and transaction processing. The distributed architecture of a SAN also enables it to offer higher levels of performance and availability than any other storage medium today. By dynamically balancing loads across the network, SANs provide fast data transfer while reducing I/O latency and server workload. The benefit is that large numbers of users can simultaneously access data without creating bottlenecks on the local area network and servers.

SANs are the best way to ensure predictable performance and 24x7 data availability and reliability. The importance of this is obvious for companies that conduct business on the web and require high volume transaction processing. Another example would be contractors that are bound to service-level agreements (SLAs) and must maintain certain performance levels when delivering IT services. SANs have built in a wide variety of failover and fault tolerance features to ensure maximum uptime. They also offer excellent scalability for large enterprises that anticipate significant growth in information storage requirements. And unlike direct-attached storage, excess capacity in SANs can be pooled, resulting in a very high utilization of resources. There has been much debate in recent times about choosing SAN or NAS in the purchasing decision, but the truth is that the two technologies can prove quite complementary. Today, SANs are increasingly implemented in conjunction with NAS. With SAN/NAS convergence, companies can consolidate block-level and file-level data on common arrays.

Even with all the benefits of SANs, several factors have slowed their adoption, including cost, management complexity and a lack of standardization. The backbone of a SAN is management software. A large investment is required to design, develop and deploy a SAN, which has limited its market to the enterprise space. A majority of the costs can be attributed to software, considering the complexity that is required to manage such a wide scope of devices. Additionally, a lack of standardization has resulted in interoperability concerns, where products from different hardware and software vendors may not work together as needed. Potential SAN customers are rightfully concerned about investment protection and many may choose to wait until standards become defined.

Conclusion

With such a variety of information storage technologies available, what is the best way to determine which one is right for your organization? DAS, NAS and SAN all offer tremendous benefits, but each is best suited for a particular environment. Consider the nature of your data and applications. How critical and processing-intensive are they? What are your minimum acceptable levels of performance and availability? Is your information sharing environment localized, or must data be distributed across the enterprise? IT professionals must make a comprehensive assessment of current requirements while also keeping long-term business goals in mind.

Like all industries, storage networking is in a constant state of change. It's easy to fall into the trap of choosing the emerging or disruptive storage technology at the time. But the best chance for success comes with choosing a solution that is cost-correct and provides long term investment protection for your organization. Digital assets will only continue to grow in the future. Make sure your storage infrastructure is conducive to cost-effective expansion and scalability. It is also important to implement technologies that are based on open industry standards, which will minimize interoperability concerns as you expand your network.